The invention relates to an automatic reversal and stop mechanism primarily for use in the tape drive of a tape recorder for automatically reversing direction of rotation of rotating members and/or stopping such members during their operation.
As is well recognized, a tape recorder is generally provided with drive means which is adapted to drive a capstan roller or tape reel in either forward or reverse direction, and the drive means internally includes means for starting, stopping or reversing rotating members. Considering a tape reel drive for a cassette tape recorder, a control mechanism for automatically reversing or stopping rotary members generally comprises means for sensing the tape end in some way, including applying a marking member such as a silver paper to the tape end or previously recording a particular electrical signal thereon. However, a separate provision of sensing means adds to the complexity of the mechanism.
It is also known to detect a sudden increase in the tape tension at the end of taking up the tape. At this end, a sensing member such as a roller or plunger is maintained in sliding contact with a travelling tape so that it may be ejected in response to the sudden increase in the tape tension when the tape end is reached, thereby producing a displacement which can be utilized to operate on an actuator of a switch, for example. While this results in a substantial simplification of construction, it still requires a space for the provision of elements which are used to detect and utilize the displacement, and additionally, the power dissipation increases also, both of which stand in the way of the miniaturization of the apparatus.